1. Field of the Invention
This invention relates to a novel shutter for a photographic camera, and more particularly to a novel shutter blind and means for operating the shutter blind to expose a film in the photographic camera. The shutter blind in accordance with the present invention does not belong to any type of the conventional shutter blind. In contrast to the conventional focal plane shutter which "moves" along the focal plane, the shutter blind of this invention "shrinks" and "expands" along the focal plane.
2. Description of the Prior Art
In photographic cameras, it has long been desired that the number of parts incorporated into various mechanisms in the camera body should be reduced to simplify the structure of the camera and lower the cost of manufacting thereof. Further, from the viewpoint of the size of the camera also, it is desirable to simplify the various mechanisms in the camera body. Particularly, the shutter mechanism is considerably complicated, and accordingly, the mechanism thereof is always desired to be simplified as much as possible.
Conventional focal plane shutters employ a flexible shutter blind wound on a spring drum. In order that the flexible shutter blind may resist an instantaneous tension exerted thereon, the shutter blind must be made of tough material. In addition, in order to pull the shutter blind wound on a spring drum by overcoming the force of the spring, means for operating the shutter blind must have a great force. Further, the camera which employs such a shutter mechanism has a defect in that the camera body is apt to be accidentally moved by the shock caused by the instantaneous tension exerted on the shutter blind. The space occupied by the spring drum is still large and is desired to be reduced.